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MiCOM Agile P441, P442 & P444
Distance Protection Systems

The MiCOM Agile P441, P442 and P444 numerical full scheme distance relays provide flexible, fast and reliable protection of transmission and sub-transmission lines. They include full scheme 5-zone distance, plus aided directional earth fault (DEF) and comprehensive backup protection for utility lines and cables at all voltage levels, particularly oriented towards transmission grids.

These distance protection systems are ideal for single circuit breaker application, single and/or 3-pole tripping, and includes a full suite of monitoring, control and recording capabilities plus fault locator, autoreclose and check synchronism.

Key features:

  • Dual algorithm distance operation for maximum fault detection dependability
  • Deploy in digital substation architectures with merging units and non-conventional instrument transformers using IEC 61850-9-2 process bus
  • Distance to fault location assists dispatching of maintenance crews 
  • Full-scheme relay offers fast, discriminative response to double-circuit, cross-country and evolving faults


The Agile P441, P442 and P444 have a settable quadrilateral operating characteristic that offers consistent 0.85-1.3 cycle zone 1 operating time for general distance application. Customers have a choice of cost-effective built-in teleprotection: InterMiCOM64 at 56/64 kbit/s for direct fiber or MUX links with 2 or 3 ended applications, or EIA (RS) 232 for MODEM links in 2 ended applications. The IEC 61850 redundant Ethernet supports self healing ring, RSTP, dual homing or PRP.

Key benefits:

  • Comprehensive communication options including IEC 61850 and redundant Ethernet ports
  • IEC61850-9-2 interface option allows integration within digital substation process bus architectures
  • Variety of built-in aided schemes over 2 channels
  • Unparallelled speed, security and selectivity


P441 Line-Distance Management IED

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P442 Line-Distance Management IED

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P444 Line-Distance Management IED for Transmission

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